When a wave has a height of 5 feet and a wavelength of 15 feet then it has a wave base of 7.5 feet. Wave base is equal to the half of the wavelength so if you consider your wavelength to be 15 feet then it is divided into 2 that would give you answer of 7.5 feet.
        
                    
             
        
        
        
They Increase the surface area available for the absorption of nutrients
        
                    
             
        
        
        
Specialized cell junctions<span> occur at points of cell-cell and cell-matrix contact in all tissues.</span>
        
                    
             
        
        
        
Answer; 
A bottleneck effect
Explanation; 
When only a few individuals survive unfavorable times, thereby losing the majority of genotypes in the next generation, it is called a bottleneck effect. 
It occurs when there is a disaster of some sort that reduces a population to a small handful, which rarely represents the actual genetic makeup of the initial population.
 
        
             
        
        
        
This would be an example of negative feedback because the body isn’t trying to surpass a set point. It’s trying to maintain the amount of food in the stomach at that point.